They are worth having, maybe not to change other people's minds though, but your own.

Honest people will sometimes may have heated up conversations (that we could call discussions) with the goal of sharpening their own thoughts in persue of the truth over a given topic.

"Assume that the person you are listening to might know something you don't." is one of Jordan Peterson's 12 rules for life, and I think he's a good example of a person who tries to have productive discussions (honest conversations) with people.